Django rotates iphone image after upload

I'm working on a photo website where I want the user to be able to upload a portrait or landscape oriented photo. The maximum width should be 1250px, but the maximum height could be 1667px if it's in portrait mode. When I upload photos in portrait orientation, they show up rotated 90 degrees to the left. Is there a way using Pillow to make sure the photo stays in the correct orientation?

This is my code:

class Result(models.Model):
    result01        = models.FileField(upload_to=get_upload_file_name, null=True, blank=True)
    result01thumb   = models.FileField(upload_to=get_upload_file_name, null=True, blank=True)

    def save(self):
        super(Result, self).save()
        if self.result01:
            size = 1667, 1250
            image = Image.open(self.result01)
            image.thumbnail(size, Image.ANTIALIAS)
            fh = storage.open(self.result01.name, "w")
            format = 'png'
            image.save(fh, format)
            fh.close()

It's important that users be able to upload photos from their phones while they're mobile, so the correct orientation is really important. Is there anything I can do here?